Journal of Building Performance ISSN: 2180-2106 Volume 12 Issue 1 2021 http://spaj.ukm.my/jsb/index.php/jbp/index Universiti Kebangsaan Malaysia The Royal Institution of Surveyors Malaysia Page 39 IMPACT OF WEATHER DEPENDENT VARIABLES ON COOLING AND DEHUMIDIFICATION LOADS OF AIR-CONDITIONED OFFICE IN WARM-HUMID Eunice Akereko Adjei 1 *, Siddig Omer 2 and Samuel Amos-Abanyie 3 1 Department of Mech. Eng., Kwame Nkrumah University of Science and Technology, Ghana 2 Department of Architecture and Built Environment, University of Nottingham, UK 3 Department of Architecture, Kwame Nkrumah University of Science and Technology, Ghana *Corresponding author: euniceaa@googlemail.com Abstract Dehumidification in buildings remains a dominant contributor to cooling load in hot-humid climate zone irrespective of the cooling technology used, thus consuming much energy and also contributes to environmental impact through emission of greenhouse gases. Benchmarking and control of energy use in the design and the operation of buildings in developing countries come with much challenges. This paper used ESDL TAS Building Simulation Software to perform dynamic simulation to explore the potential reduction of dehumidification and cooling loads of an air-conditioned office building in the hot- humid climate of Ghana through a parametric study of four weather dependent variables. The combined input variables achieved a reduction of 64.28% and 58.12% in dehumidification and cooling loads respectively of the base case model. Tuning the range of the thermostat temperature and relative humidity settings demonstrated significant savings. Reducing infiltration rate arising from all leakages to a practically feasible minimum, as well as ventilation gain demonstrated appreciable savings in energy use. Tuning of vapour diffusion factor of building materials, however, did not have significant effect on the loads. The outcome of the study is expected to inform the design and operation of air- conditioned office buildings in developing countries of hot-humid climate conditions to achieve optimum energy consumption for cooling of spaces. Keywords: Air-conditioning; Dehumidification load; Ghana; Thermostatic set point; Warm-humid climate; Weather dependent variables Article history: Submitted: 12/05/2020; Revised: 16/10/2020; Accepted: 09/02/2021; Online: 01/08/2021 INTRODUCTION Energy demand for buildings continues to surge globally by nearly 3 % per annum, making the control of energy consumption in buildings a more important issue (Farzan, 2019). According to Allouhi et al. (2015) and D’Oca (2018), buildings are responsible for 30% and 55% of global energy and electricity demand respectively. Of the total energy demand by buildings, up to about 75% is consumed in space conditioning for heating and cooling (Longo et al., 2017). Vapour-compression air conditioning units are identified as the highest end-use energy service equipment and accounts for about 50% of the total energy consumed in buildings (Chua et al, 2013; Vakiloroaya et. al, 2014). In warm-humid climate zones, the vapour-compression air conditioning units are the dominant cooling techniques used for space conditioning through removal of both sensible and latent heat loads to achieve acceptable comfort levels (CIBSE Guide A). In a study on energy efficiency and cost saving opportunities in public and commercial buildings in Ghana by Opoku et al. (2019) revealed that, if the business as usual scenario is followed with low energy efficiency ratio air-conditioners, there will be the need to install electricity generation capacity of about 480 MW by 2030 to handle influx of low energy efficient air-conditioners alone. Dehumidification in buildings remains a dominant contributor to cooling load in warm-humid climate zones irrespective of the cooling technology used, thus consuming much energy and also contributes to environmental impact through emission of greenhouse gases (Chua et al, 2013; and Vakiloroaya et. al, 2014). The Global Dehumidifiers Market has projected growth rate of 7.3% from 2018 to 2023 and more consumers have shown increased inclination towards having better air quality of space (KBV Research, 2018). Dehumidifiers are an essential part of building and factory operational systems for basically extracting particles of water in the ambient air, to prevent condensation. High amounts of energy are consumed in space cooling of buildings in hot climate zones with no thermostatic control techniques, thus presenting a great potential for energy saving (Moon et al., 2011). Thermostatic control in buildings could also help occupants to both adjust to a desired comfort level whilst minimizing the environmental impact as a consequence of energy use in buildings.